Abstract

The United States general aviation fleet is aging with aircraft manufactured 35–39 years ago representing the most prevalent group. Since older aircraft are more prone to airframe corrosion, fatigue, and brittle electrical wiring, the present study was undertaken to determine whether malfunction-related accidents for general aviation aircraft manufactured between 1970 and 1984 were elevated relative to airplanes produced more recently (2000–2014).

The NTSB aviation accident database was used to identify piston-powered airplane accidents occurring over the 2005–2014 period. Aircraft manufacture year and fleet activity data were from the FAA. Statistical analyses employed contingency tables and Poisson distributions.

The proportion of malfunction-related accidents was unchanged (p = 0.219) for aircraft manufactured over the two periods (12.2%, 2005–2014; 14.3%, 1970–1984). Similarly, malfunction-related accident rates for aircraft of older and more recent vintage were comparable: 2.73 and 2.63 per 100,000 flight hours (p = 0.866). The proportion of accidents related to airframe/flight control or electrical system failures between both aircraft cohorts was statistically insignificant (p = 0.139). Malfunction-related accidents for airplanes of recent production were more likely (p < 0.001) due to manufacture deficiencies, whereas mishaps with airplanes of earlier vintage were more probably a consequence of maintenance deficiencies. Despite the fact that > 90% of aircraft in both production eras were substantially damaged/destroyed, the overwhelming majority (70–71%) of accidents involved no occupant injuries.

This study suggests that aircraft of 35–39 years of age do not carry excess risk for malfunction-related accidents in comparison with aircraft of more recent manufacture. Presumably, these findings largely reflect the success of current inspection/maintenance practices.